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From:   AceLan Kao <acelan.kao@canonical.com>
Date:   Wed, 7 Jun 2023 13:19:40 +0800
Message-ID: <CAFv23QmDNUFcPwvSQt5aUxtmHasfr8wrF72ObvcO-X19gfn=LA@mail.gmail.com>
Subject: Re: [PATCH] platform/x86: dell-laptop: Add drm module soft dependency
To:     Matthew Garrett <mjg59@srcf.ucam.org>
Cc:     =?UTF-8?Q?Pali_Roh=C3=A1r?= <pali@kernel.org>,
        Hans de Goede <hdegoede@redhat.com>,
        Mark Gross <markgross@kernel.org>,
        platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org,
        Kai-Heng Feng <kai.heng.feng@canonical.com>
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Gfx drivers(i915/amdgpu/nvidia) depend on the drm driver, so delaying
the loading of dell_laptop after drm can ease the issue the most.
Right, it's still possible to encounter the issue, unfortunately, we
do not have a better solution for it at the moment.


Matthew Garrett <mjg59@srcf.ucam.org> =E6=96=BC 2023=E5=B9=B46=E6=9C=887=E6=
=97=A5 =E9=80=B1=E4=B8=89 =E4=B8=8B=E5=8D=8812:20=E5=AF=AB=E9=81=93=EF=BC=
=9A
>
> On Wed, Jun 07, 2023 at 11:43:31AM +0800, AceLan Kao wrote:
> > From: "Chia-Lin Kao (AceLan)" <acelan.kao@canonical.com>
> >
> > dell_laptop is somethines loaded before nvidia driver, causing it to
> > create its own backlight interface before native backlight is set.
> > This results in the presence of 2 backlight interfaces in sysfs and
> > leads to the backlight can't be adjusted.
>
> It seems like this approach would still be broken if the nvidia module
> isn't available at the time the dell module is loaded?